SEATTLE NAS, WASHINGTON

Period of Record General Climate Summary - Growing Degree Days

Station:(457468) SEATTLE NAVAL AIR STN
From Year=1929 To Year=1970
Growing Degree Days for Selected Base Temperature (F)
Base Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual
40 M 81 118 173 307 497 629 780 774 626 423 191 113 4714
40 S 81 200 373 680 1177 1807 2587 3361 3987 4410 4601 4714 4714
45 M 20 36 59 162 342 479 625 619 476 269 79 33 3199
45 S 20 56 115 277 619 1098 1723 2343 2819 3088 3167 3199 3199
50 M 1 5 10 55 194 329 470 464 326 131 17 3 2007
50 S 1 7 17 72 266 595 1065 1530 1856 1987 2004 2007 2007
55 M 0 0 0 12 80 183 315 310 181 40 1 0 1123
55 S 0 0 1 13 93 276 591 900 1082 1122 1123 1123 1123
60 M 0 0 0 2 23 69 165 158 68 7 0 0 492
60 S 0 0 0 2 25 94 259 417 485 492 492 492 492
Corn Growing Degree Days
50 M 9 28 55 123 237 334 468 463 336 169 43 14 2278
50 S 9 37 92 215 452 786 1254 1717 2052 2221 2264 2278 2278
M = Monthly Data
S - Running sum of monthly data.
Growing Degree Day units are computed as the difference between the daily average temperature and the base temperature. (Daily Ave. Temp. - Base Temp.) One unit is accumulated for each degree Fahrenheit the average temperature is above the base temperature. Negative numbers are discarded. Example: If the days high temperature was 95 and the low temperature was 51, the base 60 heating degree day units is ((95 + 51) / 2) - 60 = 13. This is done for each day of the month and summed.
Corn Growing Degree Day units have the limitations that the maximum daily temperatures greater than 86 F are set to 86 F and minimums less than 50 F are set to 50 F.
Table updated on Oct 31, 2012
Months with 5 or more missing days are not considered
Years with 1 or more missing months are not considered

Western Regional Climate Center, wrcc@dri.edu